Method and apparatus for surveying bore holes



Sept. 13, 1932 I. ROMAN IBTHOD AID APPARATUS FOR SURVEYING BORE HOLES Filed July 5, 1930 J INV NTOR ATTORNE Patented Sept. 13, 1932 UNITED STATES PATENT OFFICE mwm now, or wm'onanon, raw meat, assronoa 'ro onomsrcn.

nnsasncn ooaroaarxon, or m. ronx, it. x. A I conroaanox or m JERSEY mnon AND APPARATUS 1'03 SURVEYING BOB] HOLE Application fled July 8,

This invention relates toa method and aparatus for surveying bore holes and particuarly to a method and apparatus for surveying bore holes for oil and gas wells.

An object of the invention is to provide a simple, accurate, inexpensive and eflicient method and device for measuring the straightness and the degree of deviation from the vertical of a hole bored into the ground; and, while the invention is intended particularly for use in oil and gas wells, it may be used in any kind of wells, such as artesian wells. In drilling'wells to great depths for the purpose of producing gas, oil, etc., the intention is to drill the holes straight down so that they descend vertically into the earth,but in practice straight boring has been found extremely difiicult, and holes are often very crooked and will deviate hundreds of feet after drilling to depths of three or four thousand feet. As a consequence, the hole may have deviated so that its bottom is located beneath adjacent property, or when effort is made to locate wells within 200 or 300 feet of each other to completely cover an oil-bearing territory, the exploration is uncertain and may have left part of the territory completely untouched, as well as causing great unnecessary expense. The herein described invention eliminates this uncertainty as to the exact location of the bottom of the hole and all unnecessary expense in drilling.

An apparatus by means of which m. method may be used comprises a casing whic may be lowered into the hole by means of a cable and containing therein a mechanism whereby is photographed or otherwise recorded the position of two compass needles located near opposite ends of the casing and so mounted as to come to rest in a vertical position. From the relative positions of these two compass needles on the photograph, the angle between the true vertical and the direction of the bore hole may be easily deduced, and the direction of the bone hole calculated. The method of myinvention consists in recording the respective positions of these needles at the top of the hole, where the true north is known, and then lowering the casing the length of the distance between the 1980. Serial 110. 466,588.

two needles, and again recording the respective positions of the needles, and repeating this 0 ration the entire depth of the hole. By this means, any deflection of a needle due to interference with the normal magnetic field, by the presence of ore bodies or by other causes, may be checked against the present position of the other needle, or against the position of the same needle at an earlier or later reading and on making proper allowance for such deflection, the actual direction of the bore hole may be determined.

In the accompanying drawing, Fig. 1 is a vertical section through an apparatus embodying the invention, the apparatus being shown in a well hole, and Fig. 2 is a fragmentary portion of a photographic film containing images of the magnetic needle.

In Fig. 1, 10 indicates the hole or bore in the earth into which, by means of the cable 11, the tube or shell 12 is lowered. The tube 12 is preferably made or 100 feet long and batteries 13, which effect the illumination of the incandescent lamp 14, being connected thereto by the electrical leads 15. The electrical leads 15 are likewise connected to a switch 15a, actuated by a driving clock 30, to

be later referred to, which closes the electrical circuit at regular intervals of time, thereby illuminating the lamp 14. Positioned in the tube above the lamp 14, is the condensing lens 16, through which pass the rays of light from the lamp 14 in parallel beams.

Located beyond the lens and near the lower end of the tube, a magnetic. compass, A, is suspended, beingmounted in the gimbals 17 and 18, the outer of which 17, is pe ndicularly pivoted to the axis in the wal s of the tube 12 at the points 19, and the inner of which, 18, is pivoted at right angles thereto in the sides of the outer gimbal at the points 20. The inner gimbal in turn supports the spindle 21, which is vertically pivoted in the jeweled bearings 22 and 23, the lower bearing 23 being connected to the inner gim- V check on this invention,

flected' by other magnetic forces, but as a deflection is provided by this.

the true north can be easily ascer- And as the spindles 21 and 211), I supported 'in gimbals, constantly seek'a vertical position, due to 'grav1ty,'1t s thereby possible to calculate the angle between the true vertical and the actual directained at any time.-

.tion of the tube 12 and the bore hole, from the respective recorded positions and the lengths tarily,

llumination of the lamp 14.

' The same clock mechanism 28,

of the two compass needles on the aphic film.

' Above the indicating mechanism, near the top of the tube 12, a camera film 27 or means for making a photographic record is arranged, driven y the clock mechanism 28, and appropriate gears 29, 30, 31, 32 and.33. attached to the electrical leads 15, also'actuates the switch 15a and closes the electrical circuit which provides the brief illumination at regular intervals of time of the lamp 14. I

P to'- The lamp 14, the point of intersection of the two axes of rotation of the gimbals 17 and 18, and 17b and 18b and the center point of the camera fihn 27 arepreferably positioned in the direct line of the axis of the tube 12, so that the axis of the camera coincides with the direction of the'bore hole at any point of observation. v

The above, described mechanism is made useof, as follows: The driving clock 28 is set in motion, and is so adjusted that the. electrical circuit is closed for a brief interval of time at regular intervals as desired, as every two'minutes, for.instance. The closing of the circuit illuminates the lamp 14 momenand the beam of light passing 'in parallel rays through thecondensing' lens 15, causes the compass needles 25 and 25b to cast a shadow of their position upon the camera film 27, and a photographic record is made thereon. Fig. 2 is-a reproduction of a section of the photographic film showing a, record of the relative'positionof these nee-.

dles. Thefilm 27 is driven by the driving clock 28 at intermittent rate,such that a new rtion of the film will be exposed each I the lamp 14 pass in'para'll'el beams in the same direction as the axis .of the tube 12, and likewise of Since .the light rays fromthe tube i2, a second B,--is suspended-,--likewise and any cast by I a deviation of the bore hole from the vertical.

the bore hole 10, and since spindles 21 and 21b maintain a constant vertical position due to the force of gravity and consequently the needles 25 and 25b attached thereto maintainia I constant horizontal position, it will be seen that the relative positions both in angularity, space and length of the needles 25 and 25b appearing upon the photograph becomes a means of measuring the degree of deviation of the tube 12 and the bore 10 from the true vertical and the direction-in which the deviation takes place at the particular Ifthe axis of direction of the tube and the bore hole are vertical, the

point measured.

shadows of the two needles, of course, will coincide, and will photograph as a single needle, except for the variations in the teeth and. variations from the normal magnetic field .of the earth. But when there is a deviation from the vertical of the tube and'bore hole,- and since the direction of the needles 25 and 251) are either kept constant,fin the true north, or the degree of deflection from the true north due to interference, may be easily ascertained by means of this invention, measurements between the lines forming the needles, and the length ofthese lines become measurements by simple a1 braic relation of the angular deviations of t e bore hole from the vertical. Y

The method of my invention is as follows: A photographic or otherrecord is made of the respective positions of the compass needles 25 and 25?) at the top of the; ground, where the true north isknown, and then the casin 12 is lowered into the bore hole 10 the leng't of the known distance between the two compasses, compass B now bein lower compass A was in a 'moment before at the previous recording, and the respective when the; lower compass A is at that point,

and the second when the upper compass B reaches the same level. If the magnetic field remains uninterfered with the entire distan ce down the bore hole, the two needles, 25 and 25?), will constantly point tothe north, departures'from an'identical shadow the two needles willclearly indicate But if the magnetic field is interfered with are detected by means of my invention, which ently alposition of the two needles is again recorded. This operation is. repeated down the. entire by the presence of magnetic ore bodies or and results in a deflection of the a enses consists in checking the positions of each needle, first, against the position of the other needle at the same moment, ,and second, against the position of the same needle at an earlier or later recording. When the differences between the respective shadows cast by the needles are due only to the deviation of the bore hole from the vertical, the shadows although separate, would still 'be arallel since they both face tothe true nort But when the differences between the respective shadows are due to the presence of ore bodies or other interferences with the magnetic field, there will be a level somewhere along the bore hole where the ore body would afl'ect one needle but not the other, and the needles then will lose their parallelism and will point in different directions. By notin when the needles first begin to point in dierent directions, proper allowance can be made for the deflection of the needles from the true north, and the actual deviation of the bore hole from the vertical precisely calculated. In this wav miscalculation due to the deflection of both needles from the true-north, when both are under the influence of the same interfering force, can be avoided, even through both needles be in parallel alinement.

' Since the apparatus is lowered into the bore holes by means of the cable 11, it is ossible to determine at any time its distance into the bore hole,'and by taking a series of observations at specific distances starting from the top of the hole and going to the bottom, it is thus possible to obtain a complete log of the direction of the entire hole, and to determine the deviation of any point in the hole with reference to the top. The driving clock 30 is set in synchronism with another-clock or watch in the hands of the o rator located at the top of the bore hole. y observation two compasses, and again recording the relative position of the needles.

2. A method of surveying bore holes by use of two magnetic compasses definitely spaced one above the other and su ported for constant vertical position of axis, which method comprises recording the relative positions of the needles atone level, lowering the two compasses a distance equivalent to the distance between the two com asses, and a ain recording the relative positlon of the n les.

3. A method of surveying bore holes by use of two magnetic compasses definitely spaced one above the other and su ported for constant vertical position of axis which method comprises photographically recording the relative positions of the needles at one level, lowering the two compasses a distance equivalent to the distance between the two compasses, and again hotographically recordmg the relative position of the n les.

In testimony whereof, I have signed by name to this specification.

IRWIN ROMAN.

of his clock or watch he will know the precise time at which these intervals of photographing occur and can arrange to have the apparatus located at the proper point in the bore hole at that time by simply lowering the apparatus to the point in question sufliciently in advance and allowin it to remain stationary during the period 0 photographing.

It is apparent, of course, that various modifications may be made in the method of my invention, and in the structure of the device utilizing my method, without in any way departing from defined in the appended claims. The method and apparatus mayalso be used in other ways than those specifically described.

I claim:

1. A method of surveying bore holes by use of two magnetic com definitely spaced one above the other, which comprises recording-the relative positions of the needles at one level, lowe the two compames a distance equivalent to the distance between the the spirit of the invention as 

